1. Field of the Invention
The present invention relates to an arrangement for retention and locking, notably of the retention and locking of a spare tire cradle mounted so as to pivot under the floor of an automobile and, in particular, with a lock provided with an automatically operating safety system.
2. Description of the Prior Art:
Known locks are usually operated from the interior of the trunk, either by unscrewing, with the help of the crank handle, a threaded rod furnished with a nut, or by acting manually on a pull-knob.
This operation has the effect of disengaging the retaining catch in order to free the cradle.
But when, for purposes of safety, a second catch is provided, its manipulation, following that of the principal retaining catch, can be effected only from outside the vehicle and in an inconvenient manner.
Indeed, it is necessary to bend over to locate it, then to manipulate it by hand although it is dirty with spattered mud.
Other arrangements of the threaded rod-crank handle type are known which are more sophisticated but also more costly, in which the manipulation of the safety catch occurs automatically, in the continuation of that of the retaining catch.
This approach assumes that large forces can be exerted on the threaded rod and on the lock housing, requiring a sturdy lock and therefore a costly one.
Moreover, the complexity of the mechanism and the multiplicity of small parts render the lock more subject to jamming due to fouling.